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oai:ojs.www.eurjchem.com:article/126 2011-09-30T03:44:50Z eurjchem:ART driver

Synthesis and optimization of methyl 5-acetyl-1,4-dihydro-2,6-dimethyl-4-(substituent benzylidene)pyridine-3-carboxylate Liu, Rui Dong Zhang, Jian Unsymmetrical 1 4-dihydro-Hantzsch pyridine Condensation Catalyst Cyclization Polar aprotic solvent Two 1,4-dihydro-Hantzsch pyridine derivatives were synthesized by three steps. In the condensation step, the reaction time can be shortened to 1.5 h through using H2SO4-acetic anhydride system as a catalyst rather than the acetic acid-piperidine systemin the cyclization step, the reaction time was shortened from 20 h in ethanol to 15 h in polar aprotic solvent, and the yield of two products also was increased from 43.3% and 39.7% in traditional solvent to 93.2% and 90.1% in polar aprotic solvent. Atlanta Publishing House LLC 2011-09-30 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion application/pdf https://www.eurjchem.com/index.php/eurjchem/article/view/126 10.5155/eurjchem.2.3.308-310.126 European Journal of Chemistry; Vol. 2 No. 3 (2011): September 2011; 308-310 2153-2257 2153-2249 eng https://www.eurjchem.com/index.php/eurjchem/article/view/126/PDF